for(var p in o)
   console.log(o[p]);

1. A.

   for (var i = 0;i < a.length;i++)
        console.log(a[i]);

    

2. B.

   for (int i = 0;i < a.length;i++)
        console.log(a[i]);

    

3. C.

   for (var i = 0;i <= a.length;i++)
        console.log(a[i]);

    

4. D.

   for (var i = 1;i < a.length;i++)
        console.log(a[i]);

    

Correct Answer : A